1. Field of the Invention
This invention generally relates to a voice data processing system and method, and, in particular, to a system and method for extracting local peaks as voice features from a voice time spectral pattern in the form of a frequency distribution pattern developed in a voice recognition technique.
2. Description of the Prior Art
As described in the above-identified copending application, a voice signal when plotted in the form of a frequency distribution pattern typically includes a relatively high frequency component and a relatively low frequency component. Thus, by forming a periodic signal from a detected voice signal and passing the thus formed periodic signal through a high pass filter, the high frequency component of the voice signal can be extracted and this may be used to recognize the voice signal by comparison with a set of known, stored data. In accordance with the teaching of the above-identified copending application, a frame or a set of frequency data is sampled at a particular point in time and this frame is arranged serially by inverting alternately to produce a triangular shaped periodic signal, which is then passed though a high pass filter to obtain the high frequency component or local peak of the original voice signal to be used in recognition of the input voice data.
The technique disclosed in the above-identified copennding application allows to carry out recognition of input, unknown voice at high accuracy. However, since the same frame must be used repetitively to produce a periodic signal, it requires either a high-speed system which tends to be expensive or a relatively long time for processing of a voice signal.